Malicious PDF — malware analysis report

Static analysis result for SHA-256 42c8528de7aba24c…

MALICIOUS

PDF

69.2 KB Created: 2021-09-24 19:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 915747fc8bcf4fafa967d82b5b5ecd21 SHA-1: 69d45038ed0b3ac339eec9ef3c5c55cd49cce343 SHA-256: 42c8528de7aba24cbeafcf64b1cfe54d805df700c190a6807c9e685ae87ee9f7
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document exhibits characteristics of a phishing lure, including an image-only presentation and a link farm designed to redirect users to malicious sites. The embedded JavaScript stream and the numerous external URIs, many hosted on compromised CMS uploads or disposable domains, strongly suggest an attempt to exploit users. The ClamAV detection and ML classifier further confirm its malicious nature, likely serving as a dropper or redirector for further stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://coretry.ru/uplcv?utm_term=adobe+photoshop+7.0+free+download+for+windows+7+serial+key
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/jonanapevaxixowofud.pdf
    • http://areaengineeringsrl.eu/userfiles/files/segubesozuvarixixolejusij.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1614cf62fcf936---sofikovonokozil.pdf
    • http://saaretravel.ee/images/file/71689496174.pdf
    • http://andrenickels.de/ckfinder/userfiles/files/tinaduganabe.pdf
    • http://studioriboldi.eu/userfiles/files/wenifanapi.pdf
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/sijusazara.pdf
    • http://horizonpestservices.com/userfile/zuzezekevivavu.pdf
    • https://taiwancy.com/app/webroot/userfiles/files/tivexofurudexoguxoxew.pdf
    • http://korean-school.hu/hangul/userfiles/file/foposevo.pdf
    • http://morpheus-architects.com/file_media/file_image/file/71400132016.pdf
    • http://union.travel/ckfinder/userfiles/files/56568007030.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/366e78990398418b533df013cb379679/51046592642.pdf
    • http://canshu.dlzj.net/upload/files/20210914093004400794.pdf
    • https://pelletier-tp.fr/ckfinder/userfiles/files/81875637637.pdf
    • http://franzoesischebulldoggen.eu/userfiles/file/57568943458.pdf
    • http://www.thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/pekisapujiponesabanafowi.pdf
    • http://syntra.pl/userfiles/file/36957748541.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613541b7c2043---mefumiwodolizabolis.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613627110ac61---92027696965.pdf
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614050a23a060---99304618498.pdf
    • http://195exim.com/datas/files/21996515743.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16135ece5c593d---89564078271.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000af3b.bin
b1eef2b8f31779a9400dfee3f597eddee58a41a9ad39cfa244d9c98acc1495d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF3B 14148 bytes
font_01_sfnt_off0000d295.bin
675ee6d607f3d40d2324be541c6887b23be8b32ca0df155ec04acecef556fd53
pdf-font-stream PDF embedded font (sfnt) at offset 0xD295 11244 bytes
font_02_sfnt_off0000eccc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xECCC 16792 bytes